Magnetic separator.



uors'e zsz. Patented Ian. I4, I902. a. GRUNDAL. MAGNETIC SEPABATOR.

(Application filed Apr. 14, 1900.)

(In Iddel.)

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' UNITED STATES PATENT OFFICE.

GUSTAF eRoNDAL, OF PITKARANTA, RUSSIA.

MAGNETIC SEPARATOR.

SPECIFICATION forming part of Letters Patent No. 691,262, dated January 14, 1902.

Application filed April 14, 1900.

To all whom, it may concern:

Be it known that I, GUSTA GRoNDAL, a subject of the King of Sweden and Norway, residing at Pitkaranta, Finland, Russia, have invented a new and useful Magnetic Separator, (for which I have applied for a patent in Sweden, dated January 15, 1900,) of which the following is a specification.

My invention relates to improvements in magnetic separators; and the objects of my improvements are, first, to reduce the resistance for the lines of force, thereby producing a more powerful magnetic effect than with the arrangements hitherto known; second, to produce a magnetic field with, theoretically, an almost unlimited number of poles, I although the electromagnet has only two poles, and, third, to obtain a gradual increase of the magnetism of the active face of the separator from top to bottom. I attain these objects by the apparatus illustrated in the ac-' companying drawings, in which-- Figure 1 is a vertical section along the line din Fig. 2, and Fig. 2 partly a plan and partly a horizontal section of the separator along the line a b in Fig. 1.

Similar letters refer to similar parts.

The separator consists, essentially, of two parts, viz: a stationary electromagnet A and a rotating cap B. The core of the electromagnet has the shape of a thread-roller having one-half, more or less, of each end flange cut away, and the cap is mounted concentricto the axis of the core. Thus only a portion of the cap will come in the immediate proximity of the poles. A A are brass plates for retaining the coils on that side of the core. The cap is made of brass or other magnetically indifferent material and is provided with a great number of small lamellze c 0 0 &c., of soft iron, insulated from each other. At the top of the cap there is arranged a beltpulley O, by means of which the cap is 1'0- tated. G is a casing outside the cap B. H H are tubes for water, with regulating-cocks.

When an electric current passes through the coils of a magnet, there are produced magnetic lines of force extending from the one pole to the other, as well known. In the present instance these lines of force pass through the iron lamellze located between the poles, whereby these lamellze will become magnetic. As

Serial No. 12,854. (No model.)

well known, the number of the lines of force depends within certain limits on the resistance present. The resistance being in this construction highly reduced in consequence of the lamellze, the number of the lines of force is consequently comparatively large in this case. The lamellse being arranged in the cap in' such a manner that only a portion of them pass entirely through the side of the cap, whereas the rest is covered by more or less of the brass, the distribution of the magnetism on the outside of the cap varies. The cap is less magnetic at the top and more magnetic at the bottom.

The separator works in the following manner: The sufficiently-granulated material to be separated is suspended in water and fed in through the channel D. The magnetic particles of the material fasten on the outside of the cap, and the non-magnetic material flows away through the channel E. By washing with water the magnetic particles that have fastened on the upper part of the cap are washed off downward to the lower part of the cap, and as the lamellae are of diiferent polarity in their upper and lower parts the magnetic particles during their passage along said poles of different denomination will continually be rocking and turning over, and the non-magnetic material that has been mechanically retained with the magnetic ingredients has a good opportunity to withdraw at the turning of the latter. By the rotation of the cap the lamellae are, however, oontinually removed from the poles of the magnet A, whereby the former lose their magnetism, and the magnetic material can be easilywashed away by the water from the tube H and carried away through the channel F.

I claim as my invention- 1. A magnetic separator having a rotatable non-magnetic cap, magnetic lamellae inserted in said cap, of increasing size from the point where the material first comes under their influence to the point where it leaves it, said lamellae being magnetically insulated from each other, whereby a turning of the particles to be separated is accomplished due to the change of polarity upon leaving the edge of one lamella and taking up position with the next.

2. A magnetic separator having a rotatable cap of non magnetic material, lamellae of soft iron inserted in said cap,-magnetically insulated from each other, a magnet within the cap, having poles so placed as to cause the magnetic lines of. f0rce to pass through all the lamellze from one to the next, but more strongly in one portion of the cap than in another, said lamellae being so disposed in the field as to cause their upper and lower sides to be of opposite polarity, and also opposite in polarity to the side of the next ad jacent lamella, whereby a turning of the ar: ticles to be separated is efiected.

3. A magnetic separator having a magnet with a vertical core, and substantially circular pole-pieces but cut away on one side, a cap of non-magnetizable material mounted to revolve around and envelop said core and magnet, lamellae of magnetizable material inserted in said cap but magnetically insulated from each other, means for feeding water with the material to be separated, means for revolving the cap and means for spraying water on the material at the weakest magnetic point of the revolving cap, said waterfeed andarrangementof lamellae causing the particles to turn during revolution of the cap whereby non-magnetic materials pinned down by the magnetic ones become freed and can be carried off, substantially as described.

4:. A magnetic separator characterized by the combination of the stationary electromagnet with a roller-shaped vertical core A, the flanges of which are cut away on one side, the rotatable bell-shaped cap B of magnetically indifferent material mounted concentrically to the axisof the core A, the lamellze c c of soft iron set into the wall of the cap and extending into it with increasing depth from above and downward, the feeding-channel D and the water-tubes H H, substantially as set forth. r

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

GUSTAF GRoNDAL.

Witnesses:

A. HERLITZ, M. BREITFUSS. 

